Proud of my kid

My daughter (12 and so smart) has made the decision to stop seeing her father. She wrote out a letter to tell him why she doesn’t want to go to his house for the weekend. She tried to text him multiple times stating that she doesn’t want to see him but that if he wanted to talk to her, he can text her. My daughter’s father hasn’t responded to a single text from her or myself. He’s not asked what he can do to make it better. He hasn’t done anything to help the situation. He yells and threatens. He tells my daughter that she has no choice even though he’s told her in the past that “she is old enough to speak up to her mother and ask to she him for often”. I find it ironic that she’s a big girl with her own brain until she speaks her mind and he doesn’t like what comes out of her mouth. 

I’m stuck between feeling crazy proud of her for having a back bone and standing up for what she feels, and feeling sad that the relationship my daughter has with her father is so damaged because of the way he treats her. I do my best to not speak negatively of him in front of my daughter. I don’t respond when she says negative things about him. I don’t tell her the horrible stories of what he did to me when she was too little to remember. Yet I am blamed for the lack of relationship between them. I refuse to take the responsibility here. He needs to work to resolve the damage or my daughter won’t want to have a relationship with him. I won’t force her to do things or to see people if it isn’t good for her.